Stupid!

[BDK]

OK guys, did something really stupid tonight and need some help.  Was tightening header bolts on the MACH (351) on the passengers side when the wrench slipped from my hand and conveniently landed on the positive side of the battery cable that attaches to the starter and the other side to the case of the starter (grounding things out, great short!). 

I now have no power (no headlights, interior lights, nada from starter switch in any positions, dash lights , etc.) and suspect this is a fusible link.  Can someone point to the main fusible link that would be in the wiring (a picture would be immensely helpful)?  How does one replace this as well?

Bruce

 

[midlife]

Main fusible link starts at the battery side of the starter solenoid and snakes into the main headlight harness, along with the two 90* slip-on connectors for the starter solenoid. The fusible link feels "rubbery" when normal; very spongy when burned. Will probably be fairly discolored.

 

[BDK]

Main fusible link starts at the battery side of the starter solenoid and snakes into the main headlight harness, along with the two 90* slip-on connectors for the starter solenoid.  The fusible link feels "rubbery" when normal; very spongy when burned.  Will probably be fairly discolored.

Do you have a pic Midlife?  How is it repaired usually?

 

[midlife]

No pictures; the only possible repair is to cut the wire beyond the OEM splice and replace with a new fusible link (typically 14 gauge) or replace with 10 gauge wire.

Did you find yours was bad?

 

[BDK]

No pictures; the only possible repair is to cut the wire beyond the OEM splice and replace with a new fusible link (typically 14 gauge) or replace with 10 gauge wire.

Did you find yours was bad?

I'll be checking it today, not really sure what else it could be if not the fusible link....

 

[BDK]

Well, the fusible link has conductivity from end to end, so not that.  Could it be the starter solenoid???

Bruce

 

[c9zx]

Has the battery checked good? Chuck

 

[BDK]

Battery is just fine Chuck...12.48 volts.  I replaced the starter solenoid and am going to test and see if this is what was the issue.  Anyone know how to test a suspect starter solenoid to determine if it is good or not?

Bruce

 

[BDK]

Well once I replaced the starter solenoid I then had my interior overhead light back, however if I engaged any other circuit such as headlights or put the car in the ACC position the interior light went out.  Voltage across the S terminal and top of the solenoid is full battery voltage, across the two large terminals in the crank position it drops to 8.48.  Since the behavior is near the same with both solenoids my guess is they are just fine.....ideas??

Did I fry the starter when I dropped the wrench across it????

B

 

[Don C]

Possibly one or two bad cells in your battery. The battery will show OK voltage until any load is placed on it, then drop significantly. Do a load test on it. A bad solenoid should have no effect on voltage to the rest of the car, all connections are on the battery side of the solenoid, except for the starter, which only receives voltage when the key is turned to start position and the solenoid relay is energized. The exception to this is for some PMGR aftermarket starters, which are also connected to the battery side of the solenoid.

 

[BDK]

Don,

I do have the PMGR mini starter from DB Electrical, so connections are to the + side of the solenoid.  I've been trying other things and am quite stumped.  I can undo the negative battery cable and then reconnect, dome light comes back on in car and parking lights function perfectly.

If I then go to turn the headlights on the dome light goes out and the headlights do not come on.  However, can walk back over to the battery and disconnect/reconnect the negative cable and viola, can redo the same process.  Seems like something is drawing things down but I can't figure out what.......

I had ZERO issues with my car prior to shorting the starter, so it has to be something that is now dead and drawing things down...ideas???

B

 

[Don C]

I would start by disconnecting the main power feed to the starter and see what happens. If it's still the same disconnect one other circuit at a time, until you find the problem.

 

[BDK]

Trying this. ...it is very odd...disconnecting starter did nothing....removing plug from voltage reg. To alternator did nothing. ...still working on this. ...

 

[midlife]

Possibly one or two bad cells in your battery. The battery will show OK voltage until any load is placed on it, then drop significantly. Do a load test on it. A bad solenoid should have no effect on voltage to the rest of the car, all connections are on the battery side of the solenoid, except for the starter, which only receives voltage when the key is turned to start position and the solenoid relay is energized. The exception to this is for some PMGR aftermarket starters, which are also connected to the battery side of the solenoid.

Don C has nailed it.  A dead short across a battery for a very short period of time can cause a couple of cells to go bad, yet the battery voltage reads OK until it is under load.  The fact that putting headlights on kills power to the rest of the car's lights and voltage dropping down to ~6-8V is a dead give-away (pun intended).

Replace the battery.

 

[BDK]

Possibly one or two bad cells in your battery. The battery will show OK voltage until any load is placed on it, then drop significantly. Do a load test on it. A bad solenoid should have no effect on voltage to the rest of the car, all connections are on the battery side of the solenoid, except for the starter, which only receives voltage when the key is turned to start position and the solenoid relay is energized. The exception to this is for some PMGR aftermarket starters, which are also connected to the battery side of the solenoid.

Don C has nailed it.  A dead short across a battery for a very short period of time can cause a couple of cells to go bad, yet the battery voltage reads OK until it is under load.  The fact that putting headlights on kills power to the rest of the car's lights and voltage dropping down to ~6-8V is a dead give-away (pun intended).

Replace the battery.

OK guys, I'll give this a go and see what happens.....

Bruce

 

[Don C]

When you go to the parts store take your old battery, they'll give it a load test. You'll also need it for the core charge.

 

[RacerX]

Could be corrosive build up in the battery cables at the terminal connections. They'll conduct voltage but as soon as you try to pass amps, they fail.

 

[BDK]

First off, a BIG thank you to Don C, Midlife and RacerX for their help in diagnosing the issue I was having......and the winner is "RacerX".  Indeed it was bad battery cables, but my guess is the short had melted some of the strands inside (I cut it open but did not look too bad).  Odd too since I was using 0 gauge welding wire for my connections, but the ends were not sealed so may have just corroded.....

Thanks guys...and a BIG Thanks to RacerX!......community is great for things like this!....

Bruce

 

[Jeff73Mach1]

I don't like welding cable in cars.  The sheathing isn't designed for being around things like oil and gas.

Glad you found the problem.